Leiomyoma is a benign tumor of smooth muscle which occurs most frequently in the uterus and is diagnosed in 20 to 50% of women of reproductive age. Approximately 20% of uterine leiomyomas (ULs) show a recurrent chromosomal translocation which is often the sole detectable cytogenetic aberration, suggesting that it may represent an early event in the pathogenesis of leiomyoma.